The present invention relates to wireless networks and more specifically to a method and apparatus for providing dynamic frequency selection (DFS) spectrum access to peer-to-peer wireless networks. Embodiment of the present invention provide DFS master services for peer-to-peer networks including DFS master services from a DFS master with no direct network connection of its own. Embodiments of the present invention also enable DFS peer-to-peer networks using a system that includes a standalone DFS master coupled to a client device and configured to collect and/or generate spectral information associated with a plurality of communication channels. The system includes a cloud intelligence engine that is coupled to the client device and configured to receive the spectral information via the client device. The cloud intelligence engine is further configured to determine one or more communication channels for the standalone multi-channel DFS master from the plurality of communication channels and to communicate that information to the standalone DFS master.
Wi-Fi networks are crucial to today's portable modern life. Indeed, Wi-Fi is the preferred network in the growing Internet-of-Things (IoT). But, the technology behind current Wi-Fi has changed little in the last ten years. Most Wi-Fi networks are deployed in infrastructure mode. In infrastructure mode, a base station acts as a wireless access point, and nodes (e.g., client devices) communicate through the access point. The access point often has a wired or fiber network connection to a wide-area network and may have permanent wireless connections to other nodes. Wireless access points are usually fixed, and provide service to the client nodes that are within range. Wireless clients, such as laptops, smartphones, televisions etc. connect to the access point to join the network.
Other Wi-Fi networks use peer-to-peer communication. For example, an ad hoc network is a network where stations communicate only in a peer to peer manner. In an ad hoc network, devices are not communicating through a pre-established infrastructure or network. Wi-Fi Direct is another type of network where stations communicate peer to peer. In a Wi-Fi Direct group, a group owner is established and all other devices in the network communicate with the group owner. A peer-to-peer network allows wireless devices to directly communicate with each other. Wireless devices within range of each other can discover and communicate directly without involving central access points. Peer-to-peer networks may be used, for example, by two computers so that they can connect to each other to form a network. Also video cameras may connect directly to a computer to download video or images files using a peer-to-peer network. Additionally, device connections to external monitors and device connections to drones currently use peer-to-peer networks. For example, peer-to-peer networks are used to transfer or stream media from devices like mobile phones, tablets, and computers to Wi-Fi enabled displays and televisions. As media content increases in size and frequency of use, and as the Wi-Fi spectrum becomes more crowded, users will experience increasing difficulty with conventional peer-to-peer networks. And in a peer-to-peer network without an access point, DFS channels cannot be employed since there is no access point to control DFS channel selection and/or to tell devices which DFS channels to use. The present invention overcomes this limitation.
Devices operating in the DFS channels, require active radar detection. This function is assigned to a device capable of detecting radar known as a DFS master, which is typically an access point or router. The DFS master actively scans the DFS channels and performs a channel availability check (CAC) and periodic in-service monitoring (ISM) after the channel availability check. The channel availability check lasts 60 seconds as required by the Federal Communications Commission (FCC) Part 15 Subpart E and ETSI 301 893 standards. The DFS master signals to the other devices in the network (typically client devices) by transmitting a DFS beacon indicating that the channel is clear of radar. Although the access point can detect radar, wireless clients typically cannot. Because of this, wireless clients must first passively scan DFS channels to detect whether a beacon is present on that particular channel. During a passive scan, the client device switches through channels and listens for a beacon transmitted at regular intervals by the access point on an available channel.
Once a beacon is detected, the client is allowed to actively transmit on that channel. If the DFS master detects radar in that channel, the DFS master no longer transmits the beacon, and all client devices upon not sensing the beacon within a prescribed time must vacate the channel immediately and remain off that channel for 30 minutes. For clients associated with the DFS master network, additional information in the beacons (i.e. the channel switch announcement) can trigger a rapid and controlled evacuation of the channel. Normally, a DFS master device is an access point with only one radio and is able to provide DFS master services for just a single channel. Significant problems of this approach include: (1) DFS utilization is not available in peer-to-peer networks without an access point; (2) the DFS master channel availability check time (60 seconds) required when entering a channel would render many peer-to-peer applications unusable (waiting for a peer in a Wi-Fi peer-to-peer connection to perform the DFS master role and look for radar would result in a 60-seconds wait before a file transfer or video setup even starts); and (3) in the event of a radar event or a more-common false-detect, the single channel must be vacated and the ability to use DFS channels is lost. This disclosure recognizes and addresses, in at least certain embodiments, the problems with current devices for detecting occupying signals including current DFS devices.